Studies On Germination Characteristics And Propagation Techniques Of Semi-hardwood Cuttings Of Celtis Julianae

The germination characteristics and ways to overcome dormancy of Celtis julianae seeds as well as propagation techniques of semi-hardwood cuttings of Celtis julianae were studied. The results were shown as follows:The correlation coefficient between weight of a seed and the diameter of vertical section was 0.74 and 0.99 in seeds collected from Hubei and Zhejiang province respectively, and the correlation coefficient between weight of a seed and the diameter of horizontal section was 0.56 and 0.72 respectively. The correlation coefficient between weight of a seed and the diameter of vertical section was higher than that between weight of a seed and the diameter of horizontal section. The 1000-seed weight of seeds collected from Hubei was 248.706g,and the 1000-seeds weight of seeds collected from Zhejiang was 250.235g.The seed coat of Celtis julianae had the ability of penetrating in a certain degree. The solution extracted from outer seed coat by using methanol as an agent could inhibit the germination of cabbage seeds. The viability test showed that the viability of seeds from Hubei was 54.5% and the percentage of empty seeds was 8.3%. The viability of seeds from Zhejiang was 69.4%,and the empty seeds was 10 percent.The seeds collected from Hubei and Zhejiang province could not germinate if they were not pretreated. The germination percentage of treated seeds from Zhejiang was higher than that from Hubei. The stratification at low temperature could remarkably improve germination and overcome dormancy of Celtis julianae seeds. There were significant differences in germination percentage among different stratifying periods of the same pretreatment. The effect of outdoor stratification in winter was better than stratification at 3～5℃.The pretreatments, which was arranged in an order of GA solution soaking first and then stratification, were better than the pretreatments with stratification first.The rooting rate of semi-hardwood cuttings of Celtis julianae was low. Cuttings form 2-year-old mother plants had the highest rooting rate. In Nanjing district, the best propagating time of Celtis julianae semi-hardwood cuttings was in August. The effects were better with IBA 500mg·L-1 60s,NAA 500mg·L-1 1s and ABT 1000mg·L-1 60s treating regime among different concentrations and different kinds of exogenous hormone treating, the rooting rate of those treatments reached 63.3%. The experiments on propagation using cuttings from different parts of branches showed that the rooting rate of cuttings from base part of a branch was the highest, reaching 46.7%. Orthogonal experiments showed that the treating regime was the best if the cuttings were cut semi-hardwood branches of 2-year-old mother plant, the length of cuttings were 10㎝ or 15㎝, the diameter of cuttings were middle-sized or thick and the...